A number of intermediate transfer members, such as intermediate transfer belts selected for transferring a developed image in xerographic systems, are known. For example, there are known intermediate transfer belts that contain thermosetting polyimides. The thermosetting polyimides can be costly, especially because such imides are usually subjected to curing by heating at temperatures equal to or exceeding 300° C. for extended time periods.
Also known are intermediate transfer members that include materials with characteristics that cause these members to become brittle, resulting in inadequate acceptance of the developed image, and subsequent partial transfer of developed xerographic images to a substrate like paper.
Other disadvantages that may be associated with several known intermediate transfer members relate to an unsuitable stable resistivity, and poor break strengths resulting in degradation of the developed xerographic image to be transferred from the member.
Intermediate transfer members may provide a number of advantages, such as enabling high throughput at modest xerographic machine process speeds; and improving registration of the final color toner image in color systems using synchronous development of one or more component colors with one or more transfer stations.
However, an intermediate transfer member disadvantage is that a plurality of transfer steps is usually needed, allowing for the possibility of charge exchange occurring between toner particles and the transfer member, which ultimately can lead to less than complete toner transfer, resulting in low resolution of images on the image receiving substrate and image deterioration, undesirable color shifting and color deterioration.
Attempts at controlling the resistivity of intermediate transfer members have been accomplished by, for example, adding conductive fillers such as ionic additives and/or carbon black to the outer layer of the member. However, there are problems associated with the use of such additives. In particular, undissolved additive particles frequently bloom or migrate to the surface of the polymer and cause an imperfection in the polymer. This leads to nonuniform resistivity, which in turn causes poor antistatic properties and poor mechanical strength.
Also, the ionic additives formed on the surface of the transfer member may interfere with toner release. Furthermore, bubbles may appear in the intermediate transfer member conductive polymer, some of which can only be seen with the aid of a microscope, others of which are large enough to be observed with the naked eye. These bubbles cause poor or nonuniform electrical properties and poor mechanical properties. In addition, the ionic additives themselves are sensitive to changes in temperature, humidity, and operating time. These sensitivities often limit the resistivity range. For example, the resistivity usually decreases by up to two orders of magnitude, or more as the humidity increases from about 20 to about 80 percent relative humidity, when ionic additives are present in intermediate transfer members.
There is a need for intermediate transfer members that substantially avoid or minimize the disadvantages of a number of known intermediate transfer members.
Also, there is a need for intermediate transfer member materials that have a high glass transition temperature (Tg), and which materials have minimal brittleness.
Further, there is a need for intermediate transfer members with components that can be economically and efficiently manufactured with acceptable curing times.
There is also a need for intermediate transfer members that exhibit a desirable coefficient of thermal expansion, have acceptable modulus, and possess excellent transfer capabilities.
Moreover, there is a need for intermediate transfer members with excellent wear, desirable break strengths, and acceptable abrasion resistance.
These and other needs are achievable in embodiments with the intermediate transfer members and components thereof disclosed herein.